1. Technical Field
The present invention relates to a thermal electromagnetic wave detection element, a method for producing a thermal electromagnetic wave detection element, a thermal electromagnetic wave detection device, and an electronic apparatus.
2. Related Art
Well-known thermal electromagnetic wave detection devices include pyroelectric-type, thermocouple-type, and resistance-type (bolometer-type) infrared ray detection devices, among others. In particular, a pyroelectric infrared ray detection device makes use of the fact that the amount of spontaneous polarization in a pyroelectric material changes depending on the amount of light from received infrared rays; for example, in the case of reading out with a source follower circuit, an electrical potential difference arising due to a pyroelectric current is created at both ends of a pyroelectric body, and this electrical potential difference is utilized to detect infrared rays. The pyroelectric infrared ray detection device of such description has the advantage of being superior, in terms of detection sensitivity, to other infrared ray detection devices, such as of a thermocouple-type or bolometer-type.
One known pyroelectric infrared ray detection element is, for example, an element described in Japanese Laid-open Patent Publication 2011-203167. The infrared ray detection element (pyroelectric infrared ray detector) described in Japanese Laid-open Patent Publication 2011-203167 includes a substrate, an interlayer insulating layer provided on the substrate, a support substrate provided on the interlayer insulating layer, a detection unit that is provided on the support substrate and receives infrared rays, and one pair of electrically conductive vias (columnar electrodes) that are electrically connected to one pair of electrodes of the detection unit. A void is also formed at a site below the detection units in the interlayer insulating layer, thereby achieving thermal isolation between the detection unit and the substrate. Each of the vias is positioned lower than the void, with one of the vias being arranged so as to overlap with the void as seen in plan view.
However, in the infrared ray detection element described in Japanese Laid-open Patent Publication 2011-203167, because the via is arranged so as to overlap with the void as seen in plan view, stress is concentrated on corner parts of the void in the interlayer insulating layer at such times as when the void is being formed in the interlayer insulating layer, and a concern emerges in that the interlayer insulating layer can be damaged or deformed in the vicinity of the corner parts of the void.